Q: I have 17 beautiful shrub roses lining my walk, and they have contracted rose rosette disease. All the research information I have found indicates I should rip them out immediately so they won't infect my other roses. Do you agree?
If so, do you think I could let the bed empty for this season and replant roses next spring? Initially I was devastated at the thought of ripping out my beautiful rose hedge, but if I can save my David Austins in another bed I am ready to go!

A: Ouch! That's a disease you don't want!! Rose rosette disease is caused by an unidentified virus that's not only very destructive but also contagious to just about any rose.

Even worse, there are no good controls to stop it and no way to prevent it that I know of other than by removing infected plants. I wish I had better news. The only good news is that it's not a very common disease (yet). Of course, that doesn't do you any good either!

First, make sure it's really rose rosette disease. Things like bugs and herbicide injury can cause some similar mutated growth that might not be as dire. Typical rosette symptoms are elongated canes that often are thicker than usual; deformed flowers; mutated new growth that may turn red, and sometimes excessive thorns and mottled flower color.

This isn't the easiest problem to diagnose since you may not see all of those symptoms - especially in the early going. On top of that, since the virus or virus-like infecting agent isn't known, labs can't easily do diagnostic testing.

Nevertheless, Penn State's Plant Disease Clinic may be able to nail things down for you by inspecting a plant sample. You can get details on that service by visiting your county Penn State Extension office or by going online to http://www.ppath.cas.psu.edu/Plant_Disease_Clinic.htm.

Rose rosette is thought to be spread primarily by a type of mite, so if you can control them, that might help the spread to your David Austin roses. The disease isn't soil-borne, so you have a decent chance at replanting new roses (or other plants) after the infected ones are burned or bagged for removal. However, if you let behind any infected rose roots or pieces, those could re-infect a new planting.

I'd personally be a little nervous about replanting any rose in a bed that had rosette-infected roses - even a year later. Call me chicken, but I'd be looking at something like sweetspires or spireas or caryopteris.